On Wed, Jul 10, 2013 at 04:01:49PM +1000, Dave Airlie wrote: > On Wed, Jul 10, 2013 at 7:45 AM, Rhyland Klein <rklein@xxxxxxxxxx> wrote: > > We are currently looking into exporting some information from the linux > > kernel to userspace about the GPU. This information is specific per > > board as the data can vary depending on the fuses burnt on the board. > > > > Right now we are leaning towards adding sysfs properties to our existing > > nodes to share this information. > > > > Before we write up the patches and update our userspace apps to check > > the new locations, we wanted to make sure there wasn't a more > > accepted/proper way to export information already. > > > > Right now for instance we want to export a property to say how many > > pixel pipes there are. This could then be exported in something like: > > > > /sys/bus/platform/drivers/gr3d/54180000.gr3d/num_pixel_pipes > > > > Is this the best approach to take right now or is there another way we > > should export this and similar HW specific information? > > All the x86 GPU drivers use gpu specific get param ioctls for this so far. > > e.g. drivers/gpu/drm/radeon/radeon_kms.c:radeon_info_ioctl In drm/i915 we also expose a bunch of thing to sysfs, but everything that the userspace drivers need for operation is exposed through the getparam ioctl. We add sysfs interfaces on top if there's a legit reason for the user to script changes (e.g. gpu error state collection or tuning the frequency scaling and related read-only statistics). -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
